Epicyclic gear trains are common. Polder describes variable epicyclic gear trains in his publication “A Network Theory for Variable Epicyclic Gear Trains” published in 1969 by Greve Offset N. V. Eindhoven, Netherlands, an epicyclic gear being characterised as a black box unit with three rotating elements which are effectively able to be considered as shafts since any one may comprise an input or output, represented in a mathematical mode as a “three pole” device with one linear equation for angular velocities and two linear equations for torques.
The equation for angular velocities is written in the general form and can be seen if chosen by referring to my previous invention as follows. THIS invention relates to A CONVERTER of the epicyclic type. The present application 2003204953 is a divisional of parent application No. 42515/99. Polder's network theory of variable epicyclic gear trains involves simplifying any epicyclic gear train into an equivalent involving three pole branches, usually a combination of simple three pole transmission branches and three pole epicyclic branches.
Clearly by appropriate selection of the ratios the torque and power characterisation of any epicyclic gear train can be determined in this sense the relationships involved in an epicyclic gear train are well defined. Polder suggests a number of variable epicyclic gear trains derived using his network theory. An object of the present invention is to provide an “eM Dean” gear of the epicyclic type as a useful alternative to the prior art.